All you’d need is the ability for a client to add ability to filter to specific views or modes to only use certain relays. For example, create a Twitter mode which only shows and posts notes to 140 char relays (you tell the client which relays are 140 char relays)

I think @jb55 is working on this already with Damus and filters. Not 100% for sure tho. 

 "Mode" is perfect innovative solution albeit complicated. 

 You could have a single client, tailored to the specific modes you care about: 

- Twitter (140 chars)
- Medium (long form)
- Instagram (images only)

I’m sure there are cool things you could do if you were able to customize both the event kinds, relays, etc. 

 Not sure. But I think @pinstr #pinstr does that. I can't use many options for technical limitations.